Note 12 - Fair Value of Financial Instruments (Details Textual) - USD ($)	Sep. 30, 2017	Mar. 31, 2017
Long-term Debt, Gross	$ 398,725,000	$ 332,633,000
Long-term Debt, Fair Value	398,597,000	332,926,000
Capital Lease Obligations, Total	43,722,000	39,033,000
Capital Lease Obligations, Fair Value Disclosure	$ 41,164,000	$ 37,505,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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